Is The Three Musketeers based on the book?

Yes, "The Three Musketeers" is based on the novel of the same name written by Alexandre Dumas, first published in 1844. The story follows the adventures of d'Artagnan and his friendships with the three musketeers—Athos, Porthos, and Aramis—as they navigate political intrigue and personal loyalties in 17th-century France. Various adaptations in film, television, and other media have been inspired by Dumas' classic tale, but they often take creative liberties with the original plot and characters.